With 100 million mobile subscribers, Nigeria stands among leading mobile markets in the world. Its mobile content sector is quite fascinating — this is a market where $100 apps can debut at the No.3 position on Apple’s list of top iOS apps.

Bible and Quran apps are a major feature of the Nigerian mobile content market. The evergreen “Message Bible” was launched globally in December 2009 at almost the same time as “Angry Birds.” While the raging avians achieved greater global success, “Message Bible” was a smash in Nigeria, recently returning again to No.15 among the top grossing iPhone apps. In the United States, the app didn’t even crack the top 600 at its peak.

Recently, the old war horse has been eclipsed by hot new entries like “NKJV Bible” and “Amplified Bible,” which hit No.1 last week in Nigeria. “Amplified Bible” offers more than 100 books for free, and features a range of in-app purchases such as the King James version and scriptural knowledge.

Popular Nigerian apps are expensive. Very expensive. The two best-selling bible apps among the top five apps on August 10th were each $10 — and some of the most popular in-app purchases cost as much as $35. “QuickOffice Pro” made the top-10 list with a $15 price tag, and the popular game “Chaos Rings” costs $13. Nigeria may be a poor country, but the people who can afford Apple’s (AAPL) iPhone do not chase after free apps. In contrast, 9 out of the 10 highest-grossing iPhone apps in America are free.

Bible apps may dominate, but Nigerians also hanker after luxuriously detailed, high-end fantasy games with a Japanese flavor. Both “Infinity Blade 2” and “Chaos Rings” were top-10 apps on August 10th. “Chaos Rings” was a No.1 smash in America during the spring of 2010, but faded fast due to its unusually high download price. In Nigeria, it’s still a blockbuster.

Similarly, “Infinity Blade 2” only spent a week on the U.S. top-10 list for iPhone apps generating the most revenue. But in Nigeria, it has returned to the top again and again, most recently during the first week of August 2012.

Why is the Nigerian mobile app market so inundated with $10-plus applications?

There are several explanations. First, the market may simply be immature. The American iPhone app sales charts were dominated by expensive apps in 2010. Over the past two years, app vendors realized that handing out free apps with compelling in-app purchase features is an effective strategy to maximize revenue generation. The Nigerian market may follow a similar evolution in the future.

Second, it’s possible that Nigerian consumers are using expensive apps to substitute for even more expensive purchases. Buying 10 spiritual books would cost more than buying a single bible app that comes with a hundred free books. Buying a PlayStation 3 console with a “Final Fantasy” game would cost hundreds of dollars, but buying a slick, well-produced mobile game is a tolerable substitute, even if the game is priced at a relatively steep $13.

Third, the pool of iPhone owners in Nigeria may be so narrow that it is dominated by the elite who can afford to splurge on pricey apps. Expensive apps may be a status symbol. In America, there are tens of millions of iPhone owners, many of them in sub-$50,000 annual income households. That middle-class pool of consumers slants the app charts to favor free or cheap products.

Supporting the “status symbol of a narrow elite” explanation would be the hottest new apps of August 13th. The $100 “CFA Exam Audio Series: Level II 2013” hit No.3 in the Nigerian app market, while the $70 “King James Silver Study Bible” debuted at No.7. The rather exclusive nature of a CFA study aid would seem to imply that the Nigerian app market is resting on an extremely narrow demographic footprint.

As mobile app markets outside America mature, it will be fascinating to see whether they converge with the U.S. app market or continue evolving in vastly different directions.